People especially those are scholar but non Muslim failed to understand Quran because-
a). of its delivery technique. ie the form of the Verse:
Its verse are for example the leafs of a tree. You shake the tree and collect them under the tree randomly and makes a book with those and it is the structure of the Quran.
Again a verse may contain the sayings of God, sayings of the scriber of the mother book, sayings of the angel who brought it to the prophet.
b). form and content of the mother book:
The mother book written not in any language but in a form. In a form of frequency and it contains the whole creation, death of birth of every creations but not their deeds and sayings excepts the Prophets.But not the date of destruction of the whole creation.
c). Geneses. the creation of 1st man and woman and how they came into this world:
d). lack of knowledge. and the question we are answering is in this category. ie. lack of knowledge of understanding scriptures.
"have you not seen" it is a form of conversation. Say two English man exchange their personal experiences. ... and in a phase one says, "you know...."
all Scriptures are in a form that each of them shall be understood to them it send. But may not understandable to others. its perfect example is Christians. They have no scripture but they take one which was sent to the children of Israel. Thus they failed to understand what the scripture says. example-
"It is not what goes into the mouth that makes a person unclean. It is what comes out of the mouth that makes a person unclean".-[Matthew 15:11; Mark 7:15] if we asked a christian, a jews and a Muslim that what this verse says, what will be the answer? lets see-
Christian: It says, that entering into the mouth not defile a man: but those come out of him defile."
Jew: It says, that entering into the mouth [except those forbade God] not defile a man: but those come out of him defile."
Muslim: The Jew is right as Jesus was a Jew and he came to them. So they shall understand better his word.
Now, We have to inquire- Why the answer Differs?
The Christian Just translate the words and meanings accordingly. The Meanings is 100% correct, Yet they are Wrong, because they forget one thing- the following Verse-“I was not sent except to the lost sheep of the house of Israel.”-[Mathew, 15:21-24]
Why this [Mathew, 15:21-24] remind so important?
Because Jesus applied the verse -"It is not what goes into the mouth that makes a person unclean. It is what comes out of the mouth that makes a person unclean".-[Matthew 15:11; Mark 7:15] to the Jews who knows what is forbidden by the laws so Jesus need not to cite the exceptions.
Now you may understand why Jesus called the Christians [non Jew] "DOGs" saying- It is not right to take the children's [Son of Israel] bread"[Gospel] and through it to the Dogs [non Jew]. and WARNED them [non Jew] saying: “I was not sent except to the lost sheep of the house of Israel.”-[Mathew, 15:21-24]
Because the TRUTH is- A "Neckless of PERL" [Gospel, the sayings of Jesus] never be valued by the "DOGs" [non Jew] and the "ABSOLUTE TRUTH" is that- "Every prophet when he came, borne to one nation only, which was the mark of the mercy of God. And so their words were not extended save to that people to which they were sent."
Again Scripture says in that ways because they understand properly in it in that way. For example- if a urban school boy who never seen a dove asked his teacher "what is a dove looks like?" what shall be the answer of the teacher?
The teacher answers "the dove looks like pigeon". because the teacher knows that a urban boy familiar with pigeon.
The answer may not correct according to the zoological criteria, but the wise teacher answers this way because his urban student understood dove better in that way.
And we still use some language that is nonsensical in the sense of science. for example we say sun rise and sun sets thou it never rise or sets.
Now for the Question?
Why does this verse below allegedly say that "have you not seen" How can we humans see the galaxy orbit of the sun?
Hast thou not seen how Allah causeth the night to pass into the day and causeth the day to pass into the night, and hath subdued the sun and the moon (to do their work), each running unto an appointed term; and that Allah is Informed of what ye do? Qur'an 31:29
Now, if the question for the verse 31:29, then we have to say that the asker is noting but a STUPID, because the verse not means to see the galaxy orbit of the sun, but means- The phases of Day and night that every one observes regularly.
Yet with this stupidity of the Question Asker, we are not surprised, because it is much lesser than the stupidity of sir William Muir [see, THE BEACON OF TRUTH] or, Saint Jon Damascene [see, "Heresy of the Ishmaelites"].